1. Field of the Invention
The present invention relates to a novel process for the preparation of hexaalkyldisilthiane.
Description of the Prior Art
Hexaalkyldisilthiane (e.g., hexamethyldisilthiane) are currently of interest in regard to use as solid electrolytes for rechargeable batteries. Improved processes for the manufacture of such compounds is an area of active interest.
G. Champetier et al. in Compt. rend. 234, 1985-1986 (1952) indicated that only small quantities of hexamethyldisilthiane were produced when trimethylchlorosilane and lithium sulfide were reacted with the main product (at 48% yield) being trimethylthiosilane.
More recently, G. A. Olah et al., in J. Org. Chem., Vol. 44, No. 24, pp. 4272-4275 (1979), in footnote 13, indicated that "hexamethyldisilathiane" could be prepared from sodium sulfide and chlorotrimethylsilane at high temperatures in pressure reactors but also stated that there was almost no reaction between lithium sulfide and chlorotrimethylsilane at room temperature and atmospheric pressure.
M. R. Detty et al. in J. Org. Chem. 1982, 47, 1354-1356 reiterated the above statement about the substantial nonreactivity of lithium sulfide and chlorotrimethylsilane and indicated that commercially available dilithium sulfide and chlorotrimethylsilane, when refluxed for seventy-two hours in tetrahydrofuran, gave only a 45% yield of hexamethyldisilthiane, also called "bis(trimethylsilyl)sulfide.